const { series, parallel } = require('gulp')

const task1 = done => {
    setTimeout(() => {
        console.log('task1 working~')
        done()
    }, 1000);
}

const task2 = done => {
    setTimeout(() => {
        console.log('task2 working~')
        done()
    }, 1000);
}

const task3 = done => {
    setTimeout(() => {
        console.log('task3 working~')
        done()
    }, 1000);
}

exports.foo = series(task1, task2, task3) // 创建串行任务

exports.bar = parallel(task1, task2, task3)